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Help: blue = parse found inside. Abbreviations: WS: Workspace; SO: Syntactic Object; IA/EA: Internal/External Argument; INT/EXT: interface SO post-Merge/FormCopy; Initial WS: heads that may project after LEX word lookup. ...
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Words: Mary dances
Initial WS 1: dances Mary 
WS fail: WS θS 0 < θR 2
Initial WS 2: dancenull vdance:θ:pres INFLv:3sg Mary 
WS 1: {vdance:θ:pres, dancenull} INFLv:3sg Mary 
WS 2: {Mary, {vdance:θ:pres, dancenull}} INFLv:3sg
WS 3: {Mary, {INFLv:3sg, {Mary, {vdance:θ:pres, dancenull}}}} 
Final WS: {C, {Mary, {INFLv:3sg, {Mary, {vdance:θ:pres, dancenull}}}}} 
INT/EXT: {C, {Mary, {INFLv:3sg, {Mary, {vdance:θ:pres, dancenull}}}}}
Initial Spellout: Mary 3sg pres dance
Spellout: Mary dances
Parse found: Mary dances